"The downed aircraft was of the stealth, radar-evasive type and it intended to penetrate the off-limit nuclear area in Natanz... but was targeted by a ground-to-air missile before it managed to enter the area," ISNA said, citing a statement by the Revolutionary Guards.

The Israeli military said it did not comment on foreign reports.

Israel and the West suspect Iran of planning to build a nuclear bomb. Iran has in the past often accused its Western and Israeli foes of trying to sabotage its nuclear programme, which Tehran says is peaceful.